Apparent horizon — An apparent horizon is a surface defined in general relativity as the boundary between light rays which are directed outwards and moving outwards, and those which are directed outwards but moving inwards.Apparent horizons are not invariant… … Wikipedia

apparent horizon — The visible line of demarcation between land/sea and sky … Military dictionary

apparent horizon — The visible line of demarcation between land or the sea and the sky … Aviation dictionary

Horizon — Ho*ri zon, n. [F., fr. L. horizon, fr. Gr. ? (sc. ?) the bounding line, horizon, fr. ? to bound, fr. ? boundary, limit.] 1. The line which bounds that part of the earth s surface visible to a spectator from a given point; the apparent junction of … The Collaborative International Dictionary of English

Apparent — Ap*par ent, a. [F. apparent, L. apparens, entis, p. pr. of apparere. See {Appear}.] 1. Capable of being seen, or easily seen; open to view; visible to the eye; within sight or view. [1913 Webster] The moon . . . apparent queen. Milton. [1913… … The Collaborative International Dictionary of English